feat: allow all unrestricted method numbers on accounts

[Stebalien]

This patch implements a "raw" fallback for both account types that simply accepts all methods greater than or equal to the min FRC0042 number.

Alternative to #1081

Fixes filecoin-project/ref-fvm#1518

[arajasek]

The approach looks good to me, thank you!

I think the macros look good, but I'm honestly not especially sure.

[Stebalien]

I think the macros look good, but I'm honestly not especially sure.

The best way to review macros is to try expanding them. E.g.:

fn invoke_method<RT>(
    rt: &mut RT,
    method: MethodNum,
    args: Option<fvm_ipld_encoding::ipld_block::IpldBlock>,
) -> Result<Option<fvm_ipld_encoding::ipld_block::IpldBlock>, ActorError>
where
    RT: Runtime,
    RT::Blockstore: Clone,
{
    restrict_internal_api(rt, method)?;
    match FromPrimitive::from_u64(method) {
        Some(Self::Methods::Constructor) => {
            $crate::dispatch(rt, Self::constructor, &args)
        }
        Some(Self::Methods::AuthenticateMessageExported) => {
            $crate::dispatch(rt, Self::authenticate_message, &args)
        }
        None => Self::fallback(rt, method, args),
        None => Err($crate::ActorError::unhandled_message({
            let res = $crate::fmt::format(std::fmt::Arguments::new_v1(
                &[],
                &[std::fmt::ArgumentV1::new(&(method), std::fmt::Display::fmt)],
            ));
            res
        })),
    }
}

[anorth]

I think something weird happened to the PR and I can't see any macro changes. The raw macro thing isn't on master.

1. I think this should accept all unimplemented methods. I don't think FRC-0042 should be privileged here. We left a large range below that because there could be good call for other schemes.
2. I don't think we should use the macros in these actors. The additional conceptual complexity and indirection isn't worth it. It would be better to be blindingly obvious how it works.

[Stebalien]

I think something weird happened to the PR and I can't see any macro changes. The raw macro thing isn't on master.

#1088

I think this should accept all unimplemented methods. I don't think FRC-0042 should be privileged here. We left a large range below that because there could be good call for other schemes.

What if we need to add new methods in this low method range?

[arajasek]

1. I think this should accept all unimplemented methods. I don't think FRC-0042 should be privileged here. We left a large range below that because there could be good call for other schemes.

Yeah, I'm not sure I like this idea -- we likely need some bound here, and I think the FRC-0042 range makes sense. I'm comfortable with that level of "privileging" FRC-0042.

[arajasek]

This LGTM.

[anorth]

Ok on the FRC-0042 thing: filecoin-project/FIPs#592 (reply in thread)